The artichoke uses the Fibonacci pattern to spiral the sprouts of its flowers. The Fibonacci series starts with 0 and 1, and each of the following integers is the sum of the previous two numbers. Therefore, the numbers of the Fibonacci series are the following:
0,1,1,2,3,5,8,13,21,34,55 etc.
In the Fibonacci series you can also find the next number of the series by multiplying the previous number by an irrational number, which, as the numbers get bigger and bigger, becomes approximately 1.6180339887 (or 1.6180339887...), and which is called the Golden ratio.  Furthermore, you can find the previous number of the series by multiplying the next number by approximately 0.6180339887, which is the inverse of the golden ratio (1/1.6180339887 ).
What's the link between the Artichoke and Fibonacci? The artichoke sprouts its leafs at a constant amount of rotation, which is always 222.5 degrees (in other words the distance between one leaf and the next is 222.5 degrees), and you can measure this rotation by dividing 360 degrees (a full spin) by the inverse of the golden ratio. That's why the artichoke uses the Fibonacci series.